• The KSFM Journal of Fluid Machinery
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• v.9 no.1 s.34
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• pp.32-39
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• 2006

Recently, according to the trend of small size in scale and high speed in rotation of turbomachinery, very low specific speed centrifugal pump is taking a growing interest because the pump is characterized by high head and low flow rate with convenience of manufacturing and maintenance compared with conventional positive displacement pump. However, the efficiency of the very low specific speed centrifugal pump drops rapidly with the decrease of specific speed. The purpose of this study is nor only to examine the influence of casing type on the performance of centrifugal pump in the range of very low specific speed but also to determine the proper casing type for the improvement of pump performance. The results show that circular casing is suitable for the centrifugal pump in the range of very low specific speed and the influence of impeller configuration on the pump performance is very small. Radial thrust in the circular and volute casings is considerably small in the range of very low specific speed.

• The KSFM Journal of Fluid Machinery
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• v.9 no.1 s.34
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• pp.40-46
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• 2006

Efficiency of a centrifugal pump is known to drop rapidly with a decrease of specific speed $n_s$. However, below $n_s=60\;[min^{-1},\;m^3/min,\;m]$, the pump characteristics are not yet clear. Therefore, present study is aimed to investigate the influence of large change of specific speed on the performance of a very low specific speed centrifugal pump. Moreover, influence of impeller configuration on the performance of very low specific speed pump is investigated. The results show that very low specific speed can be accomplished by reducing volute throat sectional area using circular spacer. Influence of the spacer's location and configuration in the discharge passage on the pump performance is very small. Best efficiency of very low specific speed centrifugal pump decreases proportionally to the specific speed but the best efficiency decreases on a large scale in the range of $n_s<40$. Influence of impeller configuration on the pump performance and radial thrust of centrifugal pump are considerably small in the range of extremely low specific speed $(n_s=25)$.

• Proceedings of the Korean Geotechical Society Conference
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• 2010.09c
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• pp.135-139
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• 2010

A construction technique to install the soil-bentonite (SB) cut-off wall for in-situ geoenvironmental containment by employing the trench cutting and re-mixing deep wall method is first presented in this paper. The laboratory test results on the hydraulic barrier performance of SB in relation to the chemical compatibility are then discussed. Hydraulic conductivity tests using flexible-wall permeameters as well as swell tests were conducted for SB specimens exposed to various types and concentrations of chemicals (calcium chloride, heavy fuel oil, ethanol, and/or seawater) in the permeant and/or in the pore water of original soil. For the SB specimens in which the pore water of original soil did not contain such chemicals and thus the sufficient bentonite hydration occurred, k values were not significantly increased even when permeated with the relatively aggressive chemical solutions such as 1.0 mol/L $CaCl_2$ or 50%-concentration ethanol solution. In contrast, the SB specimens containing $CaCl_2$ in the pore water had the higher k values. The excellent linear correlation between log k and swelling pressure implies that the swelling pressure can be a good indicator for the hydraulic barrier performance of the SB.

• Preventive Nutrition and Food Science
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• v.10 no.2
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• pp.191-197
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• 2005

There exist two interesting phenomena in making seafood products from surimi. When salted surimi is kept at a constant low temperature $(4\~40^{\circ}C)$, its rheological properties change from sol to gel, which is called 'setting'. Seafood processors can exploit changes that occur during setting in preparation of surimibased products, because heating at high temperatures, after the pre-heating during the setting process, enhances the gel-strength of salted surimi. Contrarily, when salted surimi or low-temperature set gel is heated at moderate temperatures $(50\~70^{\circ}C)$, a deterioration of gel is observed. The phenomenon is termed 'modori'. In the modori temperature range, heat-stable cysteine proteinases such as cathepsin B, H, Land L-Iike hydrolyze the myosins responsible for gel-formation, resulting in gel weakening modori. This article reviews molecular events occurring during gel setting that improve the quality of surimi-based products, and inhibition of modori by applying proteinase inhibitors. Application of recombinant protein technology to surimi-based products is introduced and its prospects for practical use are discussed.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2008.03a
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• pp.407-412
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• 2008

"KAGUYA"(SELENE) is a Japanese Lunar Explorer launched by H-IIA rocket from Tanegashima Space Center on 14 September 2007. The dual-mode bipropellant propulsion subsystem of KAGUYA includes two fuel tanks, an oxidizer tank, propellant and pressurant control components, twelve monopropellant 20N thrusters, eight monopropellant 1N thrusters, and a bipropellant 500N Orbit Maneuver Engine(OME). Once the KAGUYA separated from the rocket, it circled the Earth twice and traveled to the Moon, where it entered lunar orbit. All maneuvers were performed through multiple 500N OME/20N thruster firings. This paper describes the in-space performance of KAGUYA Lunar Explorer bipropellant propulsion subsystem.

• Journal of Distribution Science
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• v.19 no.3
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• pp.5-14
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• 2021

Purpose: This study aims to clarify the behavioral extraction and ability of venture merchants, who actively challenge commerce in the face of harsh living environments. Research design, data and methodology: Adopting the concept of retail functions and retail skills, this study examines how venture merchants perform retail functions, and identifies the required retail skills. This study analyzed primary data obtained through an interview with a bookstore called Lunuganga. Results: The venture merchant purchases products based on his self-assertion and creates an original "store identification." Moreover, he draws a changing "own-store customers image" and acquires "own-store customers," that is, customers acquired by him by building an original store identity. He sells products to "own-store customers" who identify with the store. The retail skills identified as required by venture merchants to carry out such retail functions were "skill to draw a store identification" and "skill to draw own-store customer image." Conclusions: Venture merchants' unique retail functions and retail skills suggest a new basis for the existence of small and medium-sized retailers. It is necessary to build a generalized theoretical hypothesis model by refining the concept presented in this paper by repeating research targeting venture merchants in the same industry and different industries.

• The Journal of Economics, Marketing and Management
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• v.6 no.1
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• pp.9-16
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• 2018

Purpose - Benefit delay type services have a characteristic of benefit delay that does not immediately appear at the time of delivery of service. Due to a characteristic of benefit delay, the customer's participation in the service delivery system is hindered, and the quality of service declines. As a result, customer satisfaction would be reduced. The purpose of this study is to construct an analytical framework to analyze a mechanism that promotes customer participation in benefit delay type services. Research design, data, and Methodology - Existing research has considered only the performance of service companies to enhance the quality of service and customer satisfaction. This study focused on customer participation as a factor affecting the quality of service and customer satisfaction and attempted to construct an analytical framework based on a theoretical perspective of motivational research. Results - By adopting the motivation theory, this research derived three concepts, the possibility of gaining benefits, the emotional experience, and the desire of benefit. And motivation is created when the three factors interact with each other. Conclusions - This paper has constructed an analytical framework for analyzing factors that promote customer participation in the benefit delay service and finally has proposed case study for further research.

• Korean Journal of Ecology and Environment
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• v.37 no.4 s.109
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• pp.406-410
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• 2004

The alkaline phosphatase activity (APA) of two dam reservoirs and inflowing streams were measured monthly in 2000. During summer months in 2001, the vertical profiles of APA and related parameters were also examined in one of the reservoirs. The APA was relatively high during the summer season in the epilimnion while it was almost invariable in the hypolimnion. A small increase in APA was observed at just above the bottom. The APA fluctuation was independent of the concentration of soluble reactive phosphorus. It was assumed that APA is not indicative of the phosphorus availability status. An examination of size-fractionated samples suggested that APA in reservoirs was attached to particles larger than $0.4{\mu}m$, whereas in streams it existed in a dissolved form. There was a positive significant correlation between chlorophyll a concentration and APA in the photic zone. In the aphotic zone, APA correlated positively with the colony count of heterotrophic bacteria, but not with microscopic total bacterial counts.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.357-357
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• 2017

The combined application of oil cake and rice bran into the soil surface was found useful for weed control in our previous pot study. The present study was undertaken to evaluate the performance of white clover (Trifolium repens L.) while incorporated in the paddy field and effects of combined fertilizer on weed control and rice yield. A plot was divided into two parts i.e. white clover incorporated and not incorporated. The nitrogen content of the incorporated white clover was $12.5gm^{-2}$. Chemical fertilizer and combined fertilizer plots were compared with non-fertilizer conditions. The mixed ratio of combined fertilizer was oil cake 1.35 and rice bran 1.0. Combined fertilizer was applied to the soil surface, and chemical fertilizer was mixed in the soil. Nitrogen application rate was $8gm^{-2}$ for any fertilizer. The weed numbers were significantly reduced in the white clover plot irrespective of application condition both at heading and harvest time. Also, weed control ability was improved by the use of combined fertilizer. In the not incorporated plot, the number of weeds was suppressed about 90% by applying combined fertilizer. The rice yield was markedly increased by the incorporation with white clover under all fertilization conditions. Contribution rates of increased rice yield by white clover and combined fertilizer were about 55% and about 25%, respectively. The rice yield was increased by the incorporation with white clover, and the number of weeds remarkably decreased as well. Also, these effects were improved due to combined application of oil cake and rice bran.

• Journal of Physiology & Pathology in Korean Medicine
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• v.26 no.4
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• pp.418-426
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• 2012

Murai Kinzan was a disciple of the great Ko-bang scholar, Yoshimasu Todo(吉益東洞). He was born in a family of doctors, he helped his father's medical works and together made an institution of medical education. He wrote many medical books such as "Yakuchozokuhen(藥徵續編)", "Idonisen'nenganmokuhen(醫道二千年眼目編)" and "Hogyokusantei(方極刪定)". He followed Yoshimasu Todo's theories that "All disease comes from a single poison" and criticized scholars such as Yoshimasu Nangai(吉益南涯) for modifying the theories of his teacher, Yoshimasu Todo. He was also influenced by Kagawa Shuuan(香川修庵) through his father, and learned medicine from Yamawaki Touyou(山脇東洋) through letters. Under the influence of these great scholars, he pursued empirical and practical medicine based on his own experience using "Shanghanlun(傷寒論)" and "Jinguiyaolue(金匱要略)" for reference. In "Yakuchozokuhen" and "Yakuchozokuhenhuroku", Murai Kinzan maintained the main frame of "Yakucho(藥徵)", Yoshimasu Todo's work, discussing in 5 categories. Medicines that are used popularly were written in "Yakucho" and "Yakuchozokuhen", therefore those books were discussed in 5 categories. However, "Yakuchozokuhenhuroku" were discussed only in 1 ~ 3 categories.